Separating families?

One of the chief objections to enforcing immigration law is that, by sending home the parents of children with U.S. citizenship, we're breaking up families. What's not mentioned, however, is that these children also have Mexican citizenship. See Article 30, section 2 of the Mexican Constitution. Their parents are fully entitled to take them home when they are deported.

So who is heartless? That would be the parents, in my opinion.